Tutorial 4: ROS 2 and MoveIt 2 Setup

Integrating the Stonedrum Robotics dexterous hand with MoveIt 2 allows you to perform complex motion planning, collision avoidance, and trajectory execution. While examples/04_ros2_demo.py shows basic launch commands, this tutorial explains the broader MoveIt 2 setup.

MoveIt 2 Setup

MoveIt 2 relies heavily on the Semantic Robot Description Format (SRDF) and the Universal Robot Description Format (URDF). To use MoveIt 2, you must configure a move group that defines the kinematic chain of the hand.

Steps to Configure: 1. Generate a URDF for your robot arm and attach the Stonedrum hand to the end-effector link. 2. Use the MoveIt Setup Assistant to generate the MoveIt 2 configuration package. 3. Define a planning group (e.g., hand) encompassing the finger joints. 4. Define End Effector (EEF) poses in the SRDF that mirror the Grasp Library (e.g., "open", "pinch").

Launch Steps

Once your MoveIt 2 configuration package is built, you can launch the stack. First, ensure the HandNode is running so joint states are available.

From your ROS 2 workspace:

# Terminal 1: Launch the hand node
ros2 launch dexterous_hand_ros2 hand.launch.py mock:=true

# Terminal 2: Launch MoveIt 2 (assuming a custom config package)
ros2 launch my_robot_moveit_config demo.launch.py

This will open RViz, allowing you to use the interactive markers to plan trajectories for the fingers and arm simultaneously.

SRDF Snippet

Here is an example snippet of how you might define the "open" pose in your SRDF file for the hand planning group:

<robot name="stonedrum_arm_hand">
    <group name="hand">
        <joint name="thumb_flex" />
        <joint name="index_flex" />
        <joint name="middle_flex" />
        <joint name="ring_flex" />
    </group>

    <!-- Define standard named states -->
    <group_state name="open" group="hand">
        <joint name="thumb_flex" value="0.0" />
        <joint name="index_flex" value="0.0" />
        <joint name="middle_flex" value="0.0" />
        <joint name="ring_flex" value="0.0" />
    </group_state>
</robot>

For more advanced MoveIt 2 configurations or custom IK solvers, contact info@stonedrum.co.